1. Field of the Invention
The present invention relates to an electrical connector, and particularly to an electrical connector having a fastening device which can be easily inserted therein without causing any damage to a housing thereof.
2. The Prior Art
Electrical connectors are often directly mounted to a printed circuit board by means of fastening devices such as board locks. At least a pair of board locks is interferentially engaged with inner walls of slots defined in a bottom surface of a housing of the connector. Resilient legs extending beyond the bottom surface of the housing are received in holes defined in the printed circuit board whereby the connector is mounted thereto. The related prior art is disclosed in Taiwan Patent Application Nos. 80204998, 80211753, and 8-210551, and U.S. Pat. Nos. 4,907,987, 5,057,027, 5,074,807, 5,080,611, 5,135,412, 5,184,963, 5,411,404, and 5,547,385.
A conventional board lock 31 disclosed in U.S. Pat. No. 5,184,963 is shown in FIG. 4. The board lock. 31 is inserted into a slot 301 defined in a housing 30 of an electrical connector 3 to mount the connector 3 onto a printed circuit board (not shown). The board lock 31 includes a main body 311, a pair of protrusions 312 projecting outward from an upper portion of the main body 312, and a pair of resilient legs 313 forming barbs 314 thereon for engaging with a hole defined in the PCB. When the board lock 31 is inserted into the slot 301, the protrusions 312 thereof will slide along the surface of inner walls 302 of the slot 301 until reaching a reception area (not labeled) whereby the board lock 31 is retained in the slot 301. Since the board lock 31 is commonly made of metal and the housing 30 is made of plastic, the board lock 31 will scrape the inner walls 302 of the slot 301 thereby wearing away the inner walls 302 to a level indicated by worn inner walls 303 thereby reducing the retentive properties between the board lock 31 and the housing 30.
Hence, an improved fastening device is requisite to eliminate the above mentioned defects of current fastening devices.